The utilization of two or more elevator cars in a single hoistway provides increased elevator service capacity in contrast with traditional, single car-per-hoistway service. However, it is inevitable that either car may need to travel too closely to another car for safety, or need to travel to a point at or beyond the current position of the other car. The capacity of the elevator system is reduced whenever one of the cars is sitting idle due to the necessity for it to wait for another one of the cars to finish providing passenger service and thereafter remove itself from impeding the travel of the first one of the cars. Either car can become the one that is sitting idle, waiting for the other.